Abstract: | AbstractA practical number is a positive integer n such that all the positive integers m ≤ n can be written as a sum of distinct divisors of n. Let (un)n≥0 be the Lucas sequence satisfying u0 = 0, u1 = 1, and un+2 = aun+1 + bun for all integers n ≥ 0, where a and b are fixed nonzero integers. Assume a(b + 1) even and a2 + 4b > 0. Also, let ![/></span> be the set of all positive integers <i>n</i> such that <i>|u<sub>n</sub>|</i> is a practical number. Melfi proved that <span class=](/na101/home/literatum/publisher/tandf/journals/content/tqma20/2019/tqma20.v042.i07/16073606.2018.1502697/20190912/images/medium/tqma_a_1502697_ilg0001.gif) ![/></span> is infinite. We improve this result by showing that #<span class=](/na101/home/literatum/publisher/tandf/journals/content/tqma20/2019/tqma20.v042.i07/16073606.2018.1502697/20190912/images/medium/tqma_a_1502697_ilg0001.gif) ![/></span>(<i>x</i>) <i>? x/</i>log <i>x</i> for all <i>x ≥</i> 2, where the implied constant depends on <i>a</i> and <i>b</i>. We also pose some open questions regarding <span class=](/na101/home/literatum/publisher/tandf/journals/content/tqma20/2019/tqma20.v042.i07/16073606.2018.1502697/20190912/images/medium/tqma_a_1502697_ilg0001.gif) ![/></span>.</td>
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